Process of forming alcohols



Patented Feb. 1, 1944 2.340.687 PROCESS OF FORMING ALOOHOLS Wyoming, andSamoa E.

assigno Albert s. Richardson, Taylor, (miclnnati, Procter and Gamble NoDrawing;

Ohio,

rstoThe Company, Ivorydale, Ohio, a corporation of Ohio ApplicationApril 13, 1942, crial No. 438,852

. 8 Claims. (CL 260-638) Our invention relates to a process for formingv alcohols by reacting hydrogen with certain metallic salts ofcarboxylic acids.

The present application is a continuation inpart of our applicationsSer. Nos. 380,072 and 380,073, both filed February 21, 1941. The firstof these disclosed a general process for forming alcohols and esters byhydrogenating the corremeans of forming higher alcohols, which maycontain unsaturated carbon-carbon linkages ii the starting materials areunsaturated. Such a process, which is not dependent upon added metallicor metal oxide catalysts, has grcatadvantages over previously describedmethods of maksponding carboxylates of certain metals at hightemperature and pressure; and the second disclosed a similar processdirected specifically to I forming unsaturated alcohols and esters fromcorresponding unsaturated carboxylates or certain metals.

Among the carboxylates which respond to the process of the abovementioned applications are those of cadmium. When subjected to reactionwith hydrogen under the conditions of our general process cadmium soaps,for example, are converted to alcohols and esters corresponding to thefatty acid radical of these soaps, with liberation of metallic cadmiumand water:

If the B group of the carboxylate contains one or more double carbonbonds,

application are based upon our discovery that when the cadmium of thesoaps, in this process, is replaced inpart by any one or more of themetals, chromium, nickel, or copper, the proportionate yield of alcoholis greatly increased and the yield of esters is decreased. Stateddifferently, mixtures of metallic soaps comprising cadmium soaps andsoaps of any of these three metals give higher yields of alcohol than docadmium soaps alone. Furthermore, we have found that if the fatty acidradicals of the soaps are unsaturated, the process yields principallyunsaturated alcohols. The hydrogenation of nickel carboxylates is notclaimed herein, being claimed specifically in our continuing applicationSer. No. 488,736, filed May 2'7, 1943.

Thus our present process provides an improved build up the pressure inferred to as oleic acid,"

hours. The bomb was ing higher fatty alcohols. The reaction is rapid,the yields of the desired product are high, and the metals are readilyrecoverable for reuse in making fresh lots of carboxylates forhydrogenation.

The following examples will illustrate typical small scale applicationsof our process. In each of these examples the hydrogenation was carriedout in a reaction vessel consisting of a stainless steel bomb of 300cubic centimeters capacity. The mixed'fatty acids present in commercialoleic acid, or red oil," are for convenience reand the alcoholsresulting from the process are referred to as "oleyl alcohol.

The extent of the reduction of the carboxyl group is calculated from thesaponiflcation value of the original oleic acid and the saponificatlonvalue of the acid-washed, water washed, and dried reaction product. Theper cent total alcohol in the acid washed (and water washed and dried)product is determined either by calculation irom the hydroxyl valuedetermined on the unsaponiflable matter in the acid washed prodnot, orby calculation from the acid value, 39,-.

not is saponifled.

Example L-cadmium oleate and chromium oleate were separately prepared-bytreating solutions of "red oil" sodium soaps with solutions of cadmiumnitrate and chromium sulfate, respectively, and washing and drying theprecipitated metallic soaps. this cadmium oleate and 50 grams of thischromium cleate was placed in the reaction bomb at room temperature. airvessel by admitting hydrogen and venting the bomb, and then hydrogen wasintroduced to the bomb to about 1800 pounds per square inch. The bombwas sealed and heated to about 340 C. The contents were agitated byrocking the bomb, while maintaining a pressure of 3500 pounds per squareinch by adding more hydrogen when necessary, for three then allowed tocool to A mixture of 50 grams of was displaced from this a a temperatureconvenient for handling, excess gas pressure was released. and thenon-gaseous organic contents were removed, boiled with a aqueoussolution of hydrochloric or other suitable mineral acid, water washeduntil free from mineral acid, and dried.

This acid washed product was found to contain slightly over 90% of freeand combined oleyl alcohol having an iodine value slightly under 90.

Free alcohol was obtained from the acid washed material by reactingfatty acids and esters in this material with caustic alkali, extractingwith ether, and distilling off this solvent. The step of separating thefree alcohol from the alkali soap may alternatively be accomplished bydistillation or by any other convenient method.

Example 2.-A mixture of 90 grams of cadmium oleate and 10 grams ofnickel oleate was subjected of hydrogenation under conditions similar tothose of Example 1, except that the hydrogen pressure was maintained at4000 pounds per square inch and the time .of agitation at elevatedreaction temperature and pressure was only one hour.

The resulting acid washe to contain 85% free and an iodine value of 75.

Example 3.-A mixture of 97.5 grams of cadmium oleate and 2.5 grams ofcopper oleate was hydrogenated under conditions similar to those ofExample 2. The acid washed product was found to contain about 88% offree and combined alcohol having an iodine value of 82. 7

The following table contains further data concerning some or the aboveexamples, together with corresponding data for other mixtures of oleatesor these metals and for oleates of each of the four metals whenhydrogenated alone.

- d product was found combined alcohol havin a,aso,ee7 v I not claimthat it is generally, although we do equally eilicient as applied suchsalts to alcohols. It is that carboxylic acids and their in thermalstability and the of our process as applied to production of the higheralcohols is due in large part to the resistance of the salts or. thefatty acids to decomposition by side reactions under the conditionsemplayed in our process.

It will be appreciated that the advantages of t o conversion of all wknown, orcourse. derivatives diller outstanding merit the instantinvention may be achieved in increas-' ing degree by the use of greateramounts of carboxylates of the preferred metals set forth herein andcorrespondingly lesser amounts of carboxylates of other metals suitablefor use in the process as more generally claimed in the parentapplications. It is, of course. essential in order to achieve abeneficial result to use substantial proportions of the carboxylates ofthe preferred metals Preferred conditions for our process include themaintenance of temperatures between about tact between the hydrogen andthe reacting salts, the maintenance of a constant supply of hydrogen.and time under these reaction conditions sufiicient for the attainmentof substantial completion of the reaction.

Having thus described our invention, what we claim and desire to secureby Letters Patent is:

1. In a process for forming alcohols, the step which consistsessentially of subjecting to reaction with hydrogen a. mixture of saltsof carboxylic acids corresponding to said alcohols, said mixture ofsalts comprising essentially carboxylates of cadmium and of at least onemetal se- Process conditions Results Pressure Time Percent alcohol I ase e as; sees as p... MI- WN was? Lbs.

as a 8 car sass ado" 1 Percent reduction oi oarboxyl grou Percent totalalcohol, free and com Iodine value of acid alcohol) obtained thereir 4Values not determined.

Our process as exemplified by the above specific applications is equallyapplicable to treatment of soaps or all fatty acids occurring in naturalvegetable, animal, and marine fats and oils. Thus carboxylates of ourpreferred metals and of fatty acids derived from coconut oil, tallow,vegetable oils, fish oils, hydrogenated oils, etc., may be treated toproduce the corresponding fatty alcohols. Similarly, our process isapplicable to hydrogenation of metallic salts or carboxylic acids ined.in acid washed product we shed product or o! unsaponiflable matteriincluding total lected from the and copper, the reaction temperatureand hydrogen pressure being sufliciently above atmospheric to efiectsubstantial reduction CH20- of said alcohols.

2. In a process for forming fatty alcohols, the step which consistsessentially of subjecting to reaction with hydrog fatty acidscorresponding to said alcohols, said group consisting of chromium" en amixture of soaps of assaoar mixture 0! soaps comprising essentiallysoaps oi cadmium and of at least one metal selected from the groupconsisting of chromium and copper, the reaction temperature and hydrogenpressure being suillciently above atmospheric to effect sub-' stantialreduction of the carboxylic group -CO0 of said soaps to the group-CH2-O- of said alcohols.

3. The process of forming fatty alcohols, which comprises subjecting toreaction with hydrogen, at a temperature between about 240 and 400 C.and at a hydrogen pressure above 2000 pounds per square inch, a mixtureoi! soaps of fatty acids corresponding to said alcohols, said mixture ofsoaps comprising essentially soaps of cadmium and of at least one metalselected from the group consisting of chromium and copper. 4. Theprocess of claim 3, in which the soaps are soaps of unsaturated fattyacids, whereby the alcohols formed are for the most part unsaturatedalcohols.

5. The process of claim 3, comprise soaps of oleic acid.

6. The process oi claim comprise soaps oi coconut oil mixed fatty acids.

in which the soaps s, in which the scars '7. The process of formingiatty alcohols which comprises subjecting to reaction with hydrogen. ata temperature between about 240 and 400 C. and at a hydrogen pressureabove 2000 pounds per square inch, a mixture'oi soaps of fatty acidscorresponding to said alcohols, said mixture consisting of soaps ofcadmium and copper.

8. The process of forming higher alcohols which comprises: subjecting toreaction with hydrogen, at a temperature between about 240 and 400 C.and at a hydrogen pressure above 2000 pounds per square inch, a mixtureof soaps of fatty acids corresponding to said alcohols, said mixture ofsoaps ,comprising essentially soaps of cadmium and of at least one metalselected from the group consisting of chromium and copper, freeing theorganic reaction products of said hydrogenating step of tree andcombined metal by treatment with mineral acid; reacting fatty acids andesters in the resulting acid washed material with caustic alkali: andseparating free alcohols from the resulting mixture.

ALBERT S. RICHARDSON. JAMES E. TAYLOR.

